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Autorun kernels and local memory

Altera_Forum
Honored Contributor II
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Let's say I have an autorun kernel that uses a local memory. Are the values stored in the local memory persistent (i.e accessible and valid when the autorun kernel restarts automatically)? 

 

So far that's the behavior I've observed but it's not clear that it's guaranteed. Naturally, in hardware I'd expect data to be persistent; but if it's not guaranteed then emulation mode might behave differently.
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Altera_Forum
Honored Contributor II
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I don't think local memory persistency is guaranteed for autorun kernels after automatic restart. I wouldn't rely on emulator's behavior in this case since the emulator has so far been quite buggy when it comes to emulating the behavior of autorun kernels. I recommend asking Altera directly via a support request, or writing a test kernel and testing it yourself.

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Altera_Forum
Honored Contributor II
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Thanks HRZ, 

 

I apologize but my post was misleading; I've observed memory persistence in hardware. I've been having issues with getting autorun kernels to restart so I've been doing workaround which causes me to lose memory persistence. This question came about as I realized my workaround causes me to lose memory persistence which then got me thinking: I have not seen anywhere that local memory persistence is guaranteed in autorun kernels.  

 

I'll put in a support request with Altera and update if/when I get a response.
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Altera_Forum
Honored Contributor II
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I have received a response from Altera: it seems they do NOT guarantee that values stored in local memory will be accessible when the autorun kernel restarts.

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DongWang-BJTU
New Contributor I
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They should define exactly how local memory behave when used in autorun kernels.

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